namespace ZB.MOM.WW.OtOpcUa.Driver.AbCip;

/// <summary>
///     Maps libplctag / CIP General Status codes to OPC UA StatusCodes. Mirrors the shape of
///     <c>ModbusDriver.MapModbusExceptionToStatus</c> so Admin UI status displays stay
///     uniform across drivers.
/// </summary>
/// <remarks>
///     <para>Coverage: the CIP general-status values an AB PLC actually returns during normal
///     driver operation. Full CIP Volume 1 Appendix B lists 50+ codes; the ones here are the
///     ones that move the driver's status needle:</para>
///     <list type="bullet">
///         <item>0x00 success — OPC UA <c>Good (0)</c>.</item>
///         <item>0x04 path segment error / 0x05 path destination unknown — <c>BadNodeIdUnknown</c>
///             (tag doesn't exist).</item>
///         <item>0x06 partial data transfer — <c>GoodMoreData</c> (fragmented read underway).</item>
///         <item>0x08 service not supported — <c>BadNotSupported</c> (e.g. write on a safety
///             partition tag from a non-safety task).</item>
///         <item>0x0A / 0x13 attribute-list error / insufficient data — <c>BadOutOfRange</c>
///             (type mismatch or truncated buffer).</item>
///         <item>0x0B already in requested mode — benign, treated as <c>Good</c>.</item>
///         <item>0x0E attribute not settable — <c>BadNotWritable</c>.</item>
///         <item>0x10 device state conflict — <c>BadDeviceFailure</c> (program-mode protected
///             writes during download / test-mode transitions).</item>
///         <item>0x16 object does not exist — <c>BadNodeIdUnknown</c>.</item>
///         <item>0x1E embedded service error — unwrap to the extended status when possible.</item>
///         <item>any libplctag <c>PLCTAG_STATUS_*</c> below zero — wrapped as
///             <c>BadCommunicationError</c> until fine-grained mapping lands (PR 3).</item>
///     </list>
/// </remarks>
public static class AbCipStatusMapper
{
    public const uint Good = 0u;
    public const uint GoodMoreData = 0x00A70000u;
    public const uint BadInternalError = 0x80020000u;
    public const uint BadNodeIdUnknown = 0x80340000u;
    public const uint BadNotWritable = 0x803B0000u;
    public const uint BadOutOfRange = 0x803C0000u;
    public const uint BadNotSupported = 0x803D0000u;
    public const uint BadDeviceFailure = 0x80550000u;
    public const uint BadCommunicationError = 0x80050000u;
    public const uint BadTimeout = 0x800A0000u;
    public const uint BadTypeMismatch = 0x80730000u;

    /// <summary>Map a CIP general-status byte to an OPC UA StatusCode.</summary>
    public static uint MapCipGeneralStatus(byte status) => status switch
    {
        0x00 => Good,
        0x04 or 0x05 => BadNodeIdUnknown,
        0x06 => GoodMoreData,
        0x08 => BadNotSupported,
        0x0A or 0x13 => BadOutOfRange,
        0x0B => Good,
        0x0E => BadNotWritable,
        0x10 => BadDeviceFailure,
        0x16 => BadNodeIdUnknown,
        _ => BadInternalError,
    };

    /// <summary>
    ///     Map a libplctag return/status code (<c>PLCTAG_STATUS_*</c>) to an OPC UA StatusCode.
    ///     libplctag uses <c>0 = PLCTAG_STATUS_OK</c>, positive values for pending, negative
    ///     values for errors.
    /// </summary>
    public static uint MapLibplctagStatus(int status)
    {
        if (status == 0) return Good;
        if (status > 0) return GoodMoreData; // PLCTAG_STATUS_PENDING
        return status switch
        {
            -5 => BadTimeout,              // PLCTAG_ERR_TIMEOUT
            -7 => BadCommunicationError,   // PLCTAG_ERR_BAD_CONNECTION
            -14 => BadNodeIdUnknown,       // PLCTAG_ERR_NOT_FOUND
            -16 => BadNotWritable,         // PLCTAG_ERR_NOT_ALLOWED / read-only tag
            -17 => BadOutOfRange,          // PLCTAG_ERR_OUT_OF_BOUNDS
            _ => BadCommunicationError,
        };
    }
}